For quick, clean, effortless and burr-free punching. Punch waste pieces are split and can be easily removed. Suitable for sheet steel (St37), plastic and aluminum. Manual and hydraulic operation. Pre-drill diameter 9.7 mm 50360183 for tension screw diameter 9.5 mm, pre-drill diameter 20.5 mm 50344030 for tension screw diameter 19 mm.